Electric precipitator’s working principle can be simply summarized as the following four processes:
1. The gas is ionized.
2. Dust is in charged state by obtaining ions.
3. Charged dust (trap) moves to the electrode direction to collect dust.
4. Rapping cleaning.
Electrical precipitator consists of two parts:
One part is the body of the electrical precipitator, flue gas completes purification process by this means, mainly by the discharge electrode (corona electrode, a negative electrode or cathode), the collecting electrode (cathode or anode), slot board, cleaning equipment, housing, into exports smoke box, ash storage systems etc;
Another part is the control device to produce high-voltage and low-voltage direct current. AC 380V and 50Hz are converted to 60kVdirrect current for dust collector. It includes high-voltage transformers, insulators and insulator chamber, rectifier, control devices.
1-positive plate (dust collection plate); 2- hopper; 3- ladder platform; 4- positive rapping device; 5- intake smoke box; 6- cap; 7- negative rapping gear; 8- vent smoke box; 9- star negative line; 10- negative rapping device; 11- discharging device; 12- positive rapping gear; 13- chassis
Electric precipitator has the following advantages:
(1) high collection efficiency.
(2) capable of handling large flow, high temperature, high pressure or corrosive gases.
(3) power consumption, low operating costs.
(4) maintenance is simple, low cost.
Electric precipitator also has the following disadvantages:
(1) large area, a large one-time investment.
(2) the nature of all kinds of different dust, dust collection effect of the electrostatic precipitator is not the same.
(3)The requirements of electric precipitator’s operation level are relatively high.
(4) The consumption of steel is large, especially the consumption of the steel sheet is large. For example: a four-field 240m2 horizontal electrostatic precipitator, the steel consumption reached more than 1000t.
Electric precipitator has different types according to different classification methods.
(1) According to the processing method of dust classification
Dry and wet
(2) According to the flow direction of the flue gas
Vertical and horizontal
(3) Classified by collecting electrode structure
Tube and plate
(4)Classified by the collecting electrode and the discharge electrode’s matching forms
Single and dual-zone area
